Minimally invasive surgical (MIS) tools and procedures are often preferred over traditional open surgical approaches due to their propensity toward reducing post-operative recovery time and leaving minimal scarring. Endoscopic surgery is one type of MIS procedure in which a surgical tool operably connected to an elongate shaft is introduced into the body of a patient through a natural bodily orifice. Laparoscopic surgery is a related type of MIS procedure in which one or more small incisions are formed in the abdomen of a patient and a trocar is inserted through each incision to form a surgical access pathway for a surgical tool and elongate shaft. Once located within the abdomen, the surgical tool may engage and/or treat tissue in a number of ways to achieve a diagnostic or therapeutic effect. Manipulation and engagement of the surgical tool may take place via various components passing through the elongate shaft.
Robotic surgery represents a specialized class of laparoscopic surgical procedures. Instead of directly engaging a surgical tool, as in traditional laparoscopic surgery, a surgeon in a robotic surgical procedure manipulates and engages the surgical tool using an electronic interface communicatively coupled to a robotic manipulator. Manipulation and engagement of a surgical tool under robotic control can allow much more precise surgical procedures to be performed in many instances. To provide natural, hand-like articulation during a robotic surgical procedure, robotic surgical tools may incorporate an articulable “wrist” that couples an end effector to the elongate shaft. As used herein, the term “end effector” refers to the clinically active portion of a surgical tool. The wrist can also facilitate an expanded and more complex range of motion than is possible with a human wrist, which can allow highly elaborate and precise surgical procedures to be performed.
The end effectors of MIS tools are often similar in design to tools used in traditional surgical procedures, with the exception of the MIS tools being sized to extend through a trocar and configured for actuation using one or more components extending through the elongate shaft. One type of MIS tool comprises a clip applier as an end effector, which can be used to ligate blood vessels, ducts, shunts, or portions of a bodily tissue during a surgical procedure. Clip appliers used in MIS procedures include a pair of movable opposed jaw members at a distal end of the surgical tool for manipulating and crimping a surgical clip (“ligation clip”) in between. In operation, a physician may position the opposed jaw members and an open surgical clip around a vessel, duct, or similar structure and actuate the surgical tool to bring the jaw members together, thereby collapsing the surgical clip to shut off fluid flow through the vessel or duct.
During the course of a MIS procedure, a surgeon may need to place multiple surgical clips in succession on one or more anatomical structures. Although MIS clip appliers may include a single surgical clip, it can be more desirable for multiple surgical clips to be housed in the clip applier to allow completion of a MIS procedure with a single insertion of the clip applier to a surgical site. Otherwise, a surgeon may have to utilize multiple clip appliers or withdraw the clip applier from a surgical site, load a new surgical clip into the end effector, and then reintroduce the clip applier to the surgical site. Both of these approaches may increase the time, complexity, cost and risk of a MIS procedure. Accordingly, clip appliers capable of housing multiple surgical clips can be desirable.
Wristed clip appliers presently available for MIS procedures have several significant limitations. The wrist architecture in conventional MIS tools generally precludes feeding finished surgical clips through the wrist to reach the opposed jaw members of the end effector. As a result, wristed clip appliers may incorporate one or more surgical clips distal to the wrist for feeding into the opposed jaw members. Because the space distal to the wrist is small, however, the number of surgical clips that may be housed in this location is rather limited. In some instances, the number of surgical clips housed distal to the wrist may be insufficient to complete a given surgical procedure. Conventional loading approaches may be similar to those described in U.S. Pat. No. 5,743,456, which is incorporated herein by reference in its entirety.
Moreover, increasing the size of the surgical tool distal to the wrist so that more surgical clips may be accommodated can be problematic in its own right. Specifically, a larger distal tool size increases the tool length undergoing articulation (i.e., a longer end effector), which can make accurate articulation more difficult. In addition, a larger tool size distal to the wrist may render the surgical tool incompatible with other components used in a surgical procedure.